[3] Sanson's first paid job was for the Forest Service in 1971, at the age of 17, as a track cutter in the Copland Valley, now Westland Tai Poutini National Park.

[3] He then completed a Bachelor of Forestry degree at the University of Canterbury, with a thesis on wilding pine in the Abel Tasman National Park.

[2] From 2002 to 2013, Sanson was based in Christchurch as the chief executive of Antarctica New Zealand, a post he admitted he held onto "a little too long", while waiting for the top role at the Department of Conservation to become available.

[8] Sanson arrived at DOC at a time when repeated budget cuts had created an unsafe work culture, culminating in the Cave Creek disaster.

[2] During his time at DOC, Sanson expanded commercial partnerships and sometimes-controversial sponsorship arrangements with companies like Fonterra and Air New Zealand.

During his tenure DOC saw significant funding increases: $76m for tourism infrastructure and predator control in 2017, $181m for biodiversity from the newly elected Labour government, and the $500m Jobs for Nature COVID-19 recovery scheme.